Many different types of visible file-card systems have been provided in the prior art. They are usually of a complicated and, therefore, expensive structure. A well-known type includes a holder or tray with a flat back and channels at its side edges in which spring-pressed pins or wires, attached to the cards, are projected. These cards are, consequently, mounted for sliding displacement along the channels. In addition, there is a tendency for the pins and wires to bend and become inoperative or for the pins to drop out of the channels due to the flexibility of the wires. Also, it is relatively difficult to insert and remove the pins.